I have a 6" semi- flexible stainless steel chimney liner pipe, about 25 feet long that I put in my chimney when adding a fireplace insert 2 years ago. I purchased this cleaning unit to be able to make the turns in the flue and not damage the liner like bristle brushes might. Though it takes a little bit of time to add each extention as you go it worked great! It knocked everthing down from the inside going up. No climbing on top of the roof. I retreived about 4 gallons of chunks and debri from my firebox thereafter. My stove was starting to let smoke out when I would open it to add wood. Now it drafts air up the chimney like it used to when new. Dont know what its longevity will be but it seems to be made well. Highly reccomended!
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